In other investigations we have observed that perinatal complications interact with genetic vulnerability in producing effects on later behavior. Consequently one of the early steps we have taken is to determine the heritability of registered criminality. Studying biological and adoptive fathers' registered criminality as a function of adoptive sons' registered criminality revealed significant genetic transmission. This will be considered in evaluating our perinatal data. In the coming year we plan to evaluate the role of perinatal factors in the delinquency expressed in a consecutive delivery population of 9006 adolescents. Perinatal information is available on magnetic tape. Delinquency information will be sought in central registers, and reports from schools. We will also explore the possibility that autonomic nervous system factors are related to the crime factors that are genetically transmitted.